Remote Validation - get the data of 2+ fields in one remote validation jquery

Hi, i'm trying to get the data of 2+ fields in one remote validation jquery but i'm newbie.

Please help me or give me some example, so far i tried jquery validate but not works

add_action( 'admin_footer', 'lh_add_livechat_js_code' );

rules: {
    chapter_number: {
        remote: {
            url: "admin-ajax.php?action=validate_chapter_number",
            type: "post",
            data: {
                chapter_number: function() { // Get chapter_number value
                    return $("#chapter_number").val();
                },
                chapter_part: function() { // Get chapter_part value
                    return $("#chapter_part").val();
                }
            }
        }
    }
}

many thanks